Lest we forget, before Tunisia grabbed all the attention with its unprecedented uprising, Sudan was going through the first phase of an unprecedented partition. Here's a report by Dan Morrison (whose book The Black Nile I reviewed a few months ago) for Slate on what transpired:

South Sudan's leaders have been outplayed by their wily northern counterparts on almost every level in the six years since a peace agreement ended generations of civil war here. In the first years of peace, southerners lost control of important ministries they'd been promised in the postwar government, of the governorships of key states, and, it is widely believed, of hundreds of millions of dollars in stolen oil profits.

Tribal violence, some of it spurred by President Omar al-Bashir's Islamist regime in Khartoum, killed nearly 1,000 people in the south last year and displaced more than 200,000. Corruption has flowered, depriving the people of this deeply impoverished region of basic health and other services.

Yesterday, none of that mattered.

Dan highlights the South now taking steps against Arabs in in territory, a story I have heard little about elsewhere:

Efforts to secure the referendum have taken a nasty turn for some Arab residents of the south, however. More than 4 million people registered to vote, among them a farmer named Adam Ismail, but Ismail won't be placing his fingerprint on a paper ballot this week.

A resident of a disputed region called Fokhar on Sudan's north-south border in Upper Nile state, Ismail and more than 1,000 other Arabs have abandoned their homes and fields and fled to the north after a campaign of intimidation by southern soldiers.

The Arab tribes of Fokhar have long enjoyed good relations with their neighbors from the Dinka tribe, Ismail said, and the locality even includes a few mixed families, but the Arabs have been viewed with hostile suspicion by local commanders of the Sudan People's Liberation Army.

A campaign of intimidation, including arrests and interrogations, night visits by uniformed gunmen, and the shooting death of one member of the community, escalated last November, after local Arabs began registering to vote. Nearly 10 percent of the community has fled north to White Nile state, abandoning their fields and some livestock.

Issandr El Amrani is a Cairo-based writer and consultant. His reporting and commentary on the Middle East and North Africa has appeared in The Economist, London Review of Books, Financial Times, The National, The Guardian, Time and other publications. He also publishes one of the longest-running blog in the region, www.arabist.net.